Photographic-printing machine



Oct. 7, 1924. 1,510,712

D. H. STEWART PHOTOGRAPHIC PRINTING MACHINE Filed Sent. 27 L922INVENTOR. Donald HJSZeWarZ,

27 ATTO NEY Patented Oct. 7, 1924.

UNITED STATES PATENT OFFICE.

DONALD H. STEWART, OF ROCHESTER, NEW YORK, ASSIGNOR T0 EASTMAN KODAKCOMPANY, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

PHOTOGRAPHIIC-PRINTING MACHINE.

Application filed September 27, 1922. Serial No. 590,806.

To all whom it may concern:

Be it known that I, DONALD H. STEWART,

a citizen of the United States of America,"

operated, being particularly adapted for use in commercial printing fromamateurs negatives. To these ends the improvements aredirectedparticularly to the means for ac tuating the platen; to the control bywhich the platen operating mechanism is caused to function; and to themeans for securing proper printing contact between the negative andpaper. With these and other objects in view which will appear from thespecification, the invention consists in certain improvements andcombinations of parts, all

as will be hereinafter more fully described, the novel features beingpointed out in the claims at the end of the specification.

It is customary in machines of this type to operate the platen in onedirection, usually down, by! hand or power, and then to move the platenback under spring pressure. This system has the disadvantage ofrequiring the greatest ower at the end of the stroke, where, for stresults, perfectly even pressure must be applied to the negative andpaper. The spring counteracts in part the power applied to the platen,and as the spring must raise the platen rapidly, there is a large amountof power wasted. When power is used, such as a magnet or motor, the sizeof the power unit'must be such that it cannot only move the platen withthe desired speed, but it must also be capable of overcoming the powerof the spring used to return the platen, thus requiring a large andpowerful power unit. With my invention, however, these difficulties areovercome, as the platen is positively driven in each direction, andthere is no spring to be put under tension. Moreover, the parts can bemade much lighter and smaller than would otherwise be necessary to dothe same work because the parts can be balanced to require but littlemotive power.

In the drawings, in which like reference characters denote like partsthroughout; Fig. l'is a section through a printing machine, constructedin accordance with, and illustrating one form of my invention;

Fig. 2 is an end elevation thereof, parts being. broken away Fig. 3 is awiring diagram;

Fig. at is a section through a machine illustrating a second embodimentof my machine; and

Fig. 5 is a detail perspective of a latch mechanism which may be usedwith my.

printer.

The printer consists of a cabinet 1, en closing the printing lamp 2, redpilot lamp 3 (Fig. 3) and reflector 4, all mounted beneath the glassprinting panel 5. A negative is placed on this panel with theprintingpaper in the usual manner, with masks if desired, and Contact issecured between these by means of'a presser back or platen. Thisconsists of a flexible pad/7 mounted on the presser back plate 6, havinglugs 8 extending up from the plate, and being slotted at 9. Rods 10,10pass through these slots to support the plate, and springs 11, 11pressing on the rods and plate serve to keep an even pressure over theprinting frame 5, regardless of the thickness of the materials laidthereon, and in addition, as a cushioning device to reduce the shock ofthe platen being rapidly lowered.

Rods 10, 10 are mounted in the side arm 12, 12 mounted upon the shaft13, being pinned thereto by pins 141, 1 1. This shaft is carried at oneend by a bracket 15 mounted upon the slanting cabinet front 16, and atthe other end in a bracket 17, which extends down through the casingfront 16, being fastened thereto by a flange 18, and having a bearing 19on the lower end. This bearing supports a stub shaft 20, upon whichthere is a gear 21 meshing with gear 22 can ried by shaft 13. A shield22 coversgear 22 for safety. By turning shaft 20 the gears 21 and 22turn shaft 13 and with it the platen 6.

The platenmoving means is operated from a source of power, and moves theplaten to a clearance position by one device, and to a printing positionby another device, which, by way of illustration, are here shown assolenoids 23 and 24, carried by suitable brackets 25 attached to a side26 of the cabinet 1. The'cores 27 and 28 of the solenoids are eachattached to and insulated from a segment 29 carrying a stub shaft 30.Segment 29 forms a reciprocating member driven by power in eachdirection. Shaft 30 passes through a slot 31 in the bifurcated end 32 oflever 33 fastened to gear 21 by bolts 34 and 35. Slots 36, 36 permit thelever 33 to be angularly adjusted relative to the gear.

Referring to Fig. 3, the switches 37 and 38 control the solenoids, thesebeing of the type that are spring pressed into an open position. Thelinewires 39 and 40 pass current to solenoid 23 through wires a1 and d2,the latter being interrupted by switch 37. Solenoid 24: is fed throughwires 43 and 1 1, the latter wire carrying switch 38. By pressing eitherswitch the solenoid is actuated,

and by retaining pressure upon switch 24: the platen 6 is pressedcontinuously upon the printing panel, since the parts are adjusted sothat the platen contact is secured just before the core 28 reaches thelimit of movement into the coil 24. This adjustment may be made throughslots 36 and 36, and bolts 34 and 35.

The printing is here done by a single lamp 2, and a red pilot lamp 3burns continuously when switch 457 is closed enabling current to passthrough wires 4:8 and 4:9. Lamp 2, however, is controlled by the springopened switch and burns only when plunger 51 carried by the platen sidearm 12 contacts with switch 50, thus making the circuit. This plunger isin the form of an adjustable screw, notched at 52 so that a spring 53may retain the plunger in a set position. This position is obtained bycausing the lamp 2 to burn after the platen is pressed upon the printingpanel, thus insuring proper contact between the paper and negativebefore printing starts.

in Fig. 4 the machine parts which corre spond to those of Fig. 1 areindicated by the same numbers primed. Here a bell crank lever 50 iscarried by shaft 13 which carries platen 6, and there is attached toshaft 13 a disk 51 notched at 52 so as to be engaged by a latch 53pivoted at 54. to a bracket 55 and pressed into contact with the disk bya spring 56. This tends to hold the platen 6 in the open position shownwhen power is cut off from the raising solenoid 23. I connect the cores27 and 28 to end of lever 50 by means of'links 58 and 59, instead of bythe pin and slot 30, 31 of Fig. 1. These links form the reciprocatingmemher in this form.

In the machine shown in Fig. 1, I provide a lever arm 33 of such weightthat it balances the weight of the platen 6 with its associated parts sothat no latching mechanism is necessary.

If desired, a latch such as is shown in Fig. 5 may be used with notches60 and 61 located on the disk 62 in such a position that the dog 63,pressed by spring 6 1 will engage the notches thus frictionally holdingthe platen in its open or its clearance position and in its closed orprinting position.

The operation of my machine is simple and the drive is quick andpositive in. each direction. The operator may press button 37 with thefirst finger causing the platen to raise after which pressure may be released. After arranging the negative and paper on panel 5, by pressingwith the second finger upon button 38, platen 6 is lowered. Continuouspressure retains the contact, and with standard materials the averageexposure is from 1 to 3 seconds. The control of this machine can, ofcourse, be operated with one finger, but I find ityconvenient inpractice to press the buttons Y37 and 38 like the keys of a piano, withsepa rate fingers. In any event, the machine can be operatedcontinuously without fatigue. The pilot lamp 3 is always burning tofacilitate placing the negative and paper, and the printing lamp 2 isautomatically lighted and extinguished bythe movements of platen 6.

When I use the word manual in the specification and in the claims, Iuse. it in its generic sense as meaning the application of force by anypart of the operators body.

Having thus described. my invention, what I claim as new and desire tosecure by Letters Patent is:

1. In a printing machine having a printing panel and a platen movablethereover, the combination with two platen-moving devices eachincludinga source of power, of one adapted to move the platen to the printingpanel and the other adapted. to move it from the printing panel, saidplaten-moving devices having separate controls.

2. In a printing machine having a, printing p ancl and a platen movablethereover, the combination with two electro-magnetic platen-movingdevices, each including a source of power, of one adapted to move theplaten to the printing panel and the other adapted to move it from theprintingpanel, said electro-magnetic platen-moving devices havinoseparate controls.

3. 131 a printing machine having aprinting panel and a platen movable toand from an operative position thereover, the combination with-twosolenoids, of separate means for controlling the solenoids, one beingadapted to move the platen to its operative position and the other beingadapted to move it from this position.

4. In a photographic printing machine having a printing panel and aplaten movable thereover, the combination with a lever, of connectionsbetween the lever and the platen whereby the platen may be moved by thelever in two directions, separate driving devices connected to thelever, and separate controls for the driving devices, one driving devicebeing adapted to move the platen in one direction, and the other drivingdevice being adapted to move the platen in the other direction.

5. In a photographic printing machine having a, printing panel, thecombination with a platen, of a shaft to which the platen is fastened, agear on the shaft, a second gear meshing with the first gear, and meansassociated with the second gear for driving it first in one directionand then in the other.

6. In a photographic printing machine, the combination with a printingpanel, of

a platen movable to and. from an operative position thereover,connections to the platen including a lever for moving the platen, areciprocable member, and power driven means for causing this member toreciprocate, there being separate controls for governing the movements;of the reciprocable member in each direction.

7. In a photographic printing machine having a printing panel, thecombination with a platen movable to a printing posi tion thereover, andto a clearance position, of

' a reciprocable member, connections between the reciprocable member andthe platen, a source of motive power, independent manual control membersfor governing the driving devices, whereby an operator may cause adriving device to function to move the reciprocable member in thedesired direction at will.

8. A photographic printing machine, comprising a printing panel, aplaten movable into printing position on said panel and removable fromsaid panel to clearance position, means including a source of motivepower for moving said platen into and out of said positions and forretaining it in said printing position, independent manual controlmembers, connections between one of said control members and said meanswhich govern the means to move said platen to printing position andretain it therein, and connections between another of said controlmembers and said means to govern said means to remove said platen tosaid clearance position.

9. A photographic printing machine comprising a printing panel, a platenmovable into printing position on said panel and removable from saidpanel to a clearance position, a source of motive power, two separatedriving devices connected thereto, a reciprocable member operablyconnected to each of the driving devices, one being adapted to move theplaten to its printing position, the other being adapted to move theplaten to its clearance position, and separate manual controls forcausing thedriving device to function to move the reciprocable member atwill.

10. A photographic printing machine comprising a printing panel, aplaten movable into a printing position on said panel and removable fromsaid panel to a clearance position, a shaft by which the platen iscarried and with which it turns to its posi tions, means including alever for turning the shaft, a reciprocable member, connections betweenthis member and the lever for moving the latter, separate power drivendevics, one for operating the reciprocable memher in each direction, anda movable control for each power driven device adapted to normally holdthe device inoperative, means for manually moving the control to causethe device to function at will.

11. A photographic printing machine comprising a printing panel, aplatenmov able to a printing position, and to a clearance position withrespect thereto, t'Woseparate power actuated devices, connectionsbetween the platen and these devices, movable controls spring pressedinto a position in which the power actuated devices are heldinoperative, and capable of being moved manually against the springpressure into a position in which the power actuated devices willfunction.

12. A photographic: printing machine comprising a printing panel, aplaten movable to and from the panel into printing and clearancepositions, a shaft for carrying the platen, two solenoids, connectionsbetween the solenoids and the shaft including a lever, electric:circuits for the solenoids including an independent switch for eachsolenoid, means for normally holding the switches in a position to breakthe circuit, each switch being adapted to be moved to make thecircuit'and thus move the platen in one direction through one solenoid.

13. A photographic printing machine comprising a printing panel, aplaten movable to and from the panel into printing and clearancepositions, a shaft for carrying the platen, two solenoids, connectionsbetween the solenoids and the shaft including a lever, electric circuitsfor the solenoids including an independent switch for each solenoid,each switch being capable of making a circuit by manual operation, onesolenoid being adapted to move the platen to a printing position againstthe printing panel and to con tinnally press it thereon until thecircuit is broken.

14. A photographic printing machine, comprising a printing panel, aplaten movable into printing position on said panel and removable fromsaid. posit-ion, means, govern said means, when said members areincluding a source of motive power for actuated, to move said platen toprinting moving said platen to and from said printposition, retain it insaid position, and re- 10 ing position and for retaining it in said moveit from said position.

position, a plurality of members under Signed at Rochester, NewYorlgthisQQnd bodily control of the operator, connections davofSept.,1922.

between said members and said means which DONALD H. STEWART.

